Avoiding seams (was: [cairo] Best strategy for complex screen drawing)

[mental at rydia.net]

Quoting Timothée Lecomte <timothee.lecomte at ens.fr>:

> * with CAIRO_OPERATOR_SATURATE :
>        http://tipote.free.fr/wxt-saturate.png
>     No seam, but first-drawn polygons hide last ones, so to get
> the desired output, it would imply to render front-to-back and
> it would add a lot of complexity to my code...

I don't understand ... if you are already sorting your polygons
back-to-front, why is it more complicated to sort them
front-to-back instead?

-mental